sampling plan

in analytical chemistry

A predetermined procedure for the selection, withdrawal, preservation, transportation
and preparation of the portions to be removed from a population as samples. Summarizing
the test values or observations from the selected portions yields an estimate for
the concentration of an analyte or a value for a property determined with a calculable
degree of uncertainty at a specified confidence level. A sampling plan includes the designation of the number, location and size of the
portions, and instructions for the extent of compositing and for the reduction (in
amount and fineness) of the portions to a laboratory sample and to test portions. It may also contain acceptance criteria. Some sampling plans
do not include more than instructions for the statistical selection of portions to
be removed. Such plans should properly be designated as 'statistical sampling plans'.